Effect of weight loss on cardiac synchronization and proinflammatory cytokines in premenopausal obese women

Intra-left ventricular systolic asynchrony in patients with overt hyperthyroidism

Hyperthyroidism causes a variety of adverse effects on the cardiovascular system. Left ventricular (LV) asynchrony is defined as loss of the simultaneous peak contraction of corresponding cardiac segments. The aim of this study was to assess systolic asynchrony in patients with overt hyperthyroidism. Asynchrony was evaluated in 27 patients with overt hyperthyroidism and 21 controls. All the patients and controls were subjected to a tissue synchronization imaging (TSI). The time to regional peak systolic tissue velocity (Ts) in LV by the six-basal-six-mid-segmental model was measured on ejection phase TSI images and four TSI parameters of systolic asynchrony were computed. All TSI parameters of LV asynchrony increased in hyperthyroid patients compared to controls: the standard deviation (SD) of the 12 LV segments Ts (35.7±14.4 vs 20.1±10.1, P<0.0001); the maximal difference in Ts between any 2 of the 12 LV segments (111.9±40.7 vs 65.9±30.7, P<0.0001); the SD of the 6 basal LV segments (31.2±18.2 vs 16.8±9.7, P=0.01); and the maximal difference in Ts between any 2 of the 6 basal LV segments (76.6±42.0 vs 44.4±25.7, P=0.005). Patients with overt hyperthyroidism present evidence of LV asynchrony by TSI.

The relationship between adipokines, metabolic parameters and insulin resistance in patients with metabolic syndrome and type 2 diabetes

This study was designed to investigate the relationship between adipokines in metabolic syndrome and insulin resistance. Sixty male and female subjects with or without metabolic syndrome and type 2 diabetes were included. The homeostasis model assessment of insulin resistance (HOMA-IR) was calculated. Compared with lean control subjects, patients with metabolic syndrome and type 2 diabetes had lower circulating levels of total adiponectin and high molecular weight (HMW) adiponectin, and higher levels of leptin and interleukin-6 (IL-6). Total and HMW adiponectin and the adiponectin/leptin (A/L) ratio were negatively correlated with HOMA-IR. After adjusting for age and sex, leptin, IL-6 and tumour necrosis factor-alpha (TNF-alpha) were positively correlated with HOMA-IR. After also adjusting for body mass index, HOMA-IR was found to be independently associated with leptin, A/L ratio and TNF-alpha levels. In conclusion, decreased total adiponectin and HMW adiponectin and increased leptin and IL-6 levels are characteristic of patients with metabolic syndrome and type 2 diabetes.

Effects of lifestyle measures, antiobesity agents, and bariatric surgery on serological markers of inflammation in obese patients

Overweight and obesity are highly prevalent in developed countries and are also becoming more frequent in the developing world. Overweight and obese patients have elevated levels of several inflammatory markers and this inflammatory state might contribute to their increased vascular risk. We summarize the effects of lifestyle changes, antiobesity agents, and bariatric surgery on serological inflammatory markers in overweight and obese patients. Most studies showed a decrease in inflammation with all 3 interventions. However, it remains to be established whether the decrease in inflammatory markers induced by lifestyle changes or (where indicated) with antiobesity agents or bariatric surgery will translate into reduced vascular morbidity and mortality in overweight and obese patients.

The impact of metabolic syndrome on left ventricular myocardial performance

BACKGROUND

Metabolic syndrome (MetS) is common and is associated with increased cardiovascular morbidity and mortality. Recent prospective studies suggested that MetS is associated with increased risk of heart failure. In the present cross-sectional study, we examined the association between left ventricular myocardial performance with MetS.

MATERIALS AND METHODS

A total of 550 non-diabetic subjects, 275 without MetS and 275 with MetS, matched for gender, age and body mass index and free of clinically apparent macrovascular disease were studied. MetS was diagnosed using the NCEP-ATP III criteria. Left ventricular myocardial performance was assessed using the Tei index.

RESULTS

Both men and women with MetS had higher values of the Tei index, indicating worse myocardial performance, in comparison with those without MetS (p < 0.001). Participants with a cluster of more components of the MetS had higher Tei index values than those with fewer components of the MetS. In addition, among normotensive subjects, those with MetS had significantly higher Tei index values than subjects without MetS. Multivariate linear regression analysis, after adjustment for age and body mass index, demonstrated that MetS status and from the individual components of the MetS, high fasting blood glucose levels, higher blood pressure, low high density lipoprotein levels and high waist circumference were associated with worse myocardial performance.

CONCLUSION

MetS is associated with subclinical myocardial dysfunction in both men and women. Strategies to reduce the cardiovascular burden and the risk of heart failure associated with MetS should aim at prevention of the MetS and its related conditions.

Role of proinflammatory cytokines and redox homeostasis in exercise-induced delayed progression of hypertension in spontaneously hypertensive rats

Hypertension is a well-known risk factor for various cardiovascular diseases. Recently, exercise has been recommended as a part of lifestyle modification for all hypertensive patients. However, the precise mechanisms of exercise training (ExT)-induced effects on the development of hypertension are poorly understood. Therefore, we hypothesized that chronic ExT would delay the progression of hypertension in young spontaneously hypertensive rats (SHRs). In addition, we explored whether the beneficial effects of chronic ExT were mediated by reduced proinflammatory cytokines and improved redox status. We also investigated the involvement of nuclear factor-kappaB in exercise-induced effects. To test our hypotheses, young normotensive (Wistar-Kyoto) and SHRs were given moderate-intensity ExT for 16 weeks. Blood pressure was determined by the tail-cuff method, and cardiac function was assessed by echocardiography. Myocardial total reactive oxygen species and superoxide production were measured by electron paramagnetic resonance spectroscopy; tumor necrosis factor-alpha, interleukin-1beta, gp91(phox), and inducible NO synthase by real-time PCR; and nuclear factor kappaB activity by electrophoretic mobility shift assay. Chronic ExT in hypertensive rats resulted in significantly reduced blood pressure, reduced concentric hypertrophy, and improved diastolic function. ExT significantly reduced proinflammatory cytokines and inducible NO synthase, attenuated total reactive oxygen species and superoxide production, and increased antioxidants in SHRs. ExT also resulted in increased NO production and decreased nuclear factor kappaB activity in SHRs. In summary, chronic ExT delays the progression of hypertension and improves cardiac function in young SHRs; these ExT-induced beneficial effects are mediated by reduced proinflammatory cytokines and improved redox homeostasis via downregulation of nuclear factor-kappaB.

To assess, to control, to exclude: effects of biobehavioral factors on circulating inflammatory markers

Behavioral scientists have increasingly included inflammatory biology as mechanisms in their investigation of psychosocial dynamics on the pathobiology of disease. However, a lack of standardization of inclusion and exclusion criteria and assessment of relevant control variables impacts the interpretation of these studies. The present paper reviews and discusses human biobehavioral factors that can affect the measurement of circulating markers of inflammation. Keywords relevant to inflammatory biology and biobehavioral factors were searched through PubMed. Age, sex, and hormonal status, socioeconomic status, ethnicity and race, body mass index, exercise, diet, caffeine, smoking, alcohol, sleep disruption, antidepressants, aspirin, and medications for cardiovascular disease are all reviewed. A tiered set of recommendations as to whether each variable should be assessed, controlled for, or used as an exclusion criteria is provided. These recommendations provide a framework for observational and intervention studies investigating linkages between psychosocial and behavioral factors and inflammation.

Long-term weight loss decreases the nontraditional cardiovascular risk factors interleukin-18 and matrix metalloproteinase-9 in obese subjects

The objective of the study was to investigate the effect of long-term (3.2 years) weight loss on serum levels of the nontraditional cardiovascular risk factors interleukin (IL)-18 and matrix metalloproteinase (MMP)-9. Moreover, we wanted to assess the significance of the magnitude of the weight loss and evaluate the potential effects of 36 months of treatment with the lipase inhibitor orlistat on these parameters. Sixty-eight abdominally obese subjects completed 8 weeks of very low energy diet (600-800 kcal/d) followed by 36 months of randomized treatment with either orlistat or placebo together with lifestyle intervention. Serum levels of IL-18, MMP-9, and leptin were measured by flowmetric xMAP technology (Luminex, Austin, TX). Changes in the levels of IL-18, MMP-9, and leptin were similar in the orlistat and the placebo group during this study. Thus, the 2 groups were combined for further analysis. A weight loss of 8.4 +/- 8.8 kg from baseline to 3.2 years was associated with significant decreases in IL-18 (P < .001), MMP-9 (P < .01), and leptin (P < .001). Matrix metalloproteinase-9 was, however, significantly increased after 8 weeks of very low energy diet-induced weight loss (P < .05). The long-term changes in IL-18 were significantly associated with changes in body mass index independent of changes in blood pressure and lipids (P < .05). Levels and changes of IL-18 and MMP-9 were significantly positively associated at 3.2 years (P < .01). Long-term changes in leptin were significantly associated with changes in IL-18 (P < .01) at 3.2 years. Diet-induced long-term weight loss decreased IL-18 and MMP-9. The decrease in IL-18 was associated with changes in body mass index independent of changes in blood pressure and lipids, indicating that even a minor weight reduction (>5%) has beneficial effects on nontraditional cardiovascular risk markers. Orlistat treatment had no independent effects on IL-18, MMP-9, or leptin in the present study.

Addition of aerobic exercise to a weight loss program increases BMD, with an associated reduction in inflammation in overweight postmenopausal women

Increased inflammation and weight loss are associated with a reduction in bone mineral density (BMD). Aerobic exercise may minimize the loss of bone and weight loss may contribute to a decrease in cytokines. We tested the hypothesis that aerobic exercise in combination with a weight loss program would decrease circulating concentrations of inflammatory markers, thus mediating changes in BMD. This was a nonrandomized controlled trial. Eighty-six overweight and obese postmenopausal women (50-70 years of age; BMI, 25-40 kg/m(2)) participated in a weight loss (WL; n = 40) or weight loss plus walking (WL + AEX; n = 46) program. Outcome measures included BMD and bone mineral content of the femoral neck and lumbar spine measured by dual energy X-ray absorptiometry, interleukin-6, tumor necrosis factor-alpha, soluble receptors of IL-6, and TNF-alpha (sTNFR1 and sTNFR2; receptors in a subset of the population), VO(2) max, fat mass, and lean mass. Weight decreased in the WL (p < 0.001) and WL + AEX (p < 0.001) groups. VO(2) max increased (p < 0.001) after WL + AEX. There was a 2% increase in femoral neck BMD in the WL + AEX group (p = 0.001), which was significantly different from the WL group. The change in sTNFR1 was significantly associated with the change in femoral neck BMD (p < 0.05). The change in VO(2) max was an independent predictor of the change in femoral neck BMD. Our findings suggest that the addition of aerobic exercise is recommended to decrease inflammation and increase BMD during weight loss in overweight postmenopausal women.

Obesity and inflammation: the effects of weight loss

Following the discovery of TNF-α and leptin as secretory products of adipocytes in the early 1990s, subsequent obesity research focused on the new functional role of adipose tissue, as an active endocrine organ. Many more inflammatory peptides have been linked to adiposity, which ultimately characterised obesity as a state of low-grade systemic inflammation, or ‘metaflammation’ which may link obesity to its co-morbidities. The aim of the present review is to examine the effects of weight loss on inflammation in overweight and obese, but otherwise healthy, populations. Studies were broadly classified into four types (diet, physical activity, diet and physical activity combined, and surgical interventions) and discussed according to the method used to induce weight loss. All studies measured at least one obesity-related inflammatory marker (ORIM). The overall finding from the present review is that weight loss does improve inflammation in terms of both the inflammatory (C-reactive protein, TNF-α, IL-6 and leptin) and anti-inflammatory (adiponectin) ORIM. Within this, the greatest improvements in ORIM are observed in studies achieving a weight loss of at least 10 %. However, a number of methodological issues have been identified as potential limitations within the literature including the sex and age of subjects, sample size, study duration and the assessment of body composition. In conclusion, although a period of weight loss per se is capable of reversing the unfavourable inflammatory profile evident in the obese state, further studies are required to determine the time needed, in which a reduced weight is maintained, in order to benefit from improved inflammatory status long term.

Novel aspects of adipocyte-induced skeletal muscle insulin resistance

Insulin resistance in skeletal muscle is an early event in the development of diabetes with obesity being one of the major contributing factors. Conditioned medium (CM) from differentiated human adipocytes impairs insulin signalling in human skeletal muscle cells. Recent data on adipocyte-induced insulin resistance in skeletal muscle cells describes underlying mechanisms of this process. Skeletal muscle insulin resistance involves multiple pathways and irreversible changes in the expression level of critical proteins. Furthermore, the reversibility of insulin resistance could be demonstrated. Several strategies to combat insulin resistance have been developed. One recent approach to treat obesity and the metabolic syndrome is the use of endocannabinoid receptor antagonists such as rimonabant. These compounds might also reduce insulin resistance in type 2 diabetes with effects on adipose tissue and liver and possibly skeletal muscle.

The usefulness of circulating adipokine levels for the assessment of obesity-related health problems

Because the prevalence of obesity has increased dramatically in recent years, one of the key targets of public health is obesity and its associated pathological conditions. Obesity occurs as a result of white adipose tissue enlargement, caused by adipocyte hyperplasia and/or hypertrophy. Recently, endocrine aspects of adipose tissue have become an active research area and these adipose tissue-derived factors are referred to as adipokines. These adipokines interact with a range of processes in many different organ systems and influence a various systemic phenomena. Therefore, dysregulated production of adipokines has been found to participate in the development of metabolic and vascular diseases related to obesity. The obese state is also known to be associated with increased local and systemic inflammation. Adipokines influence not only systemic insulin resistance and have pathophysiological roles in the metabolic syndrome and cardiovascular disease, but also contribute toward an increase in local and systemic inflammation. Thus, circulating levels of adipokines can be used as high-throughput biomarkers to assess the obesity-related health problems, including low grade inflammation. This review focuses on the usefulness of measuring circulating adipokine levels for the assessment of obesity-related health problems.

The Impact of Prevention on Reducing the Burden of Cardiovascular Disease

Objective— Cardiovascular disease (CVD) is prevalent and expensive. While many interventions are recommended to prevent CVD, the potential effects of a comprehensive set of prevention activities on CVD morbidity, mortality, and costs have never been evaluated. We therefore determined the effects of 11 nationally recommended prevention activities on CVD-related morbidity, mortality, and costs in the United States.

Research Design and Methods— We used person-specific data from a representative sample of the US population (National Health and Nutrition Education Survey IV) to determine the number and characteristics of adults aged 20-80 years in the United States today who are candidates for different prevention activities related to CVD. We used the Archimedes model to create a simulated population that matched the real US population, person by person. We then used the model to simulate a series of clinical trials that examined the effects over the next 30 years of applying each prevention activity one by one, or altogether, to those who are candidates for the various activities and compared the health outcomes, quality of life, and direct medical costs to current levels of prevention and care. We did this under two sets of assumptions about performance and compliance: 100% success for each activity and lower levels of success considered aggressive but still feasible.

Results— Approximately 78% of adults aged 20-80 years alive today in the United States are candidates for at least one prevention activity. If everyone received the activities for which they are eligible, myocardial infarctions and strokes would be reduced by 63% and 31%, respectively. If more feasible levels of performance are assumed, myocardial infarctions and strokes would be reduced 36% and 20%, respectively. Implementation of all prevention activities would add ≈221 million life-years and 244 million quality-adjusted life-years to the US adult population over the coming 30 years, or an average of 1.3 years of life expectancy for all adults. Of the specific prevention activities, the greatest benefits to the US population come from providing aspirin to high-risk individuals, controlling pre-diabetes, weight reduction in obese individuals, lowering blood pressure in people with diabetes, and lowering LDL cholesterol in people with existing coronary artery disease (CAD). As currently delivered and at current prices, most prevention activities are expensive when considering direct medical costs; smoking cessation is the only prevention strategy that is cost-saving over 30 years.

Conclusions— Aggressive application of nationally recommended prevention activities could prevent a high proportion of the CAD events and strokes that are otherwise expected to occur in adults in the United States today. However, as they are currently delivered, most of the prevention activities will substantially increase costs. If preventive strategies are to achieve their full potential, ways must be found to reduce the costs and deliver prevention activities more efficiently.

Skeletal muscle insulin resistance induced by adipocyte-conditioned medium: underlying mechanisms and reversibility

Insulin resistance in skeletal muscle is an early event in the development of diabetes, with obesity being one of the major contributing factors. In vitro, conditioned medium (CM) from differentiated human adipocytes impairs insulin signaling in human skeletal muscle cells, but it is not known whether insulin resistance is reversible and which mechanisms may underlie this process. CM induced insulin resistance in human myotubes at the level of insulin-stimulated Akt and GSK-3 phosphorylation. In addition, insulin-resistant skeletal muscle cells exhibit enhanced production of reactive oxygen species and ceramide as well as a downregulation of myogenic transcription factors such as myogenin and MyoD. However, insulin resistance was not paralleled by increased apopotosis. Regeneration of myotubes for 24 or 48 h after induction of insulin resistance restored normal insulin signaling. However, the expression level of myogenin could not be reestablished. In addition to decreasing myogenin expression, CM also decreased the release of IL-6 and IL-8 and increased monocyte chemotactic protein-1 (MCP-1) secretion from skeletal muscle cells. Although regeneration of myotubes reestablished normal secretion of IL-6, the release of IL-8 and MCP-1 remained impaired for 48 h after withdrawal of CM. In conclusion, our data show that insulin resistance in skeletal muscle cells is only partially reversible. Although some characteristic features of insulin-resistant myotubes normalize in parallel to insulin signaling after withdrawal of CM, others such as IL-8 and MCP-1 secretion and myogenin expression remain impaired over a longer period. Thus, we propose that the induction of insulin resistance may cause irreversible changes of protein expression and secretion in skeletal muscle cells.

Prevention of heart failure: a scientific statement from the American Heart Association Councils on Epidemiology and Prevention, Clinical Cardiology, Cardiovascular Nursing, and High Blood Pressure Research; Quality of Care and Outcomes Research Interdisciplinary Working Group; and Functional Genomics and Translational Biology Interdisciplinary Working Group

The increase in heart failure (HF) rates throughout the developed and developing regions of the world poses enormous challenges for caregivers, researchers, and policymakers. Therefore, prevention of this global scourge deserves high priority. Identifying and preventing the well-recognized illnesses that lead to HF, including hypertension and coronary heart disease, should be paramount among the approaches to prevent HF. Aggressive implementation of evidence-based management of risk factors for coronary heart disease should be at the core of HF prevention strategies. Questions currently in need of attention include how to identify and treat patients with asymptomatic left ventricular systolic dysfunction (Stage B HF) and how to prevent its development. The relationship of chronic kidney disease to HF and control of chronic kidney disease in prevention of HF need further investigation. Currently, we have limited understanding of the pathophysiological basis of HF in patients with preserved left ventricular systolic function and management techniques to prevent it. New developments in the field of biomarker identification have opened possibilities for the early detection of individuals at risk for developing HF (Stage A HF). Patient groups meriting special interest include the elderly, women, and ethnic/racial minorities. Future research ought to focus on obtaining a much better knowledge of genetics and HF, especially both genetic risk factors for development of HF and genetic markers as tools to guide prevention. Lastly, a national awareness campaign should be created and implemented to increase public awareness of HF and the importance of its prevention. Heightened public awareness will provide a platform for advocacy to create national research programs and healthcare policies dedicated to the prevention of HF.

Effect of weight loss on coronary circulation and adiponectin levels in obese women

BACKGROUND

Obesity is independently associated with coronary endothelial dysfunction. Adiponectin, a protein whose circulating levels are decreased in obesity, has direct effects on vascular function. The aim of this study was to investigate in obese women the effect of sustained weight loss on coronary circulation and circulating adiponectin levels.

METHODS

Coronary flow velocity reserve (CFVR), assessed by transthoracic Doppler echocardiography (TTDE), blood pressure, lipid, glucose and insulin, HOMA scores, CRP-protein (CRP), and adiponectin parameters were investigated in forty obese pre-menopausal women and 40 healthy matched normal weight women at baseline and after sustained weight loss.

RESULTS

At baseline, the obese group had significantly higher fasting glucose (P<0.05), insulin concentrations (P<0.01), HOMA scores (P<0.001), C-reactive protein (CRP) levels (P<0.001) and lower plasma adiponectin levels (P<0.001) than the controls. CFVR was significantly lower in obese group than in the normal weight group (P<0.05). After 12 months of a multidisciplinary program of weight reduction, obese women lost at least 10% of their original weight. Fasting glucose (<0.001) and insulin concentrations (P<0.001), HOMA scores (P<0.001), CRP levels (P<0.01) were significant reduced, whereas adiponectin levels (P<0.001) and HDL cholesterol (P<0.05) showed a significant increment. CFVR value significantly improved in obese subjects (P<0.001). There was a significant correlation between changes in CFVR and changes in adiponectin levels (r=0.47, P<0.05). Multivariate analysis showed that adiponectin was the only independent predictor of change in CFVR (r=0.38, P<0.05).

CONCLUSIONS

In obese women the weight loss improves coronary circulation and increases adiponectin levels. The improvement in coronary circulation is associated with adiponectin levels.

The effects of caloric restriction- and exercise-induced weight loss on left ventricular diastolic function

Little is known about the effects of weight loss on diastolic function. Furthermore, it is not known whether both caloric restriction (CR)- and exercise (Ex)-induced weight loss have salutary effects on diastolic function. Therefore, we assessed the effects of yearlong CR ( n = 12) and Ex ( n = 13) interventions, which induced ∼12% weight loss, on diastolic function in healthy, nonobese (body mass index = 23.5–29.9 kg/m2) men and women aged 50 to 60 yr. Recordings of Doppler transmitral flow and Doppler tissue imaging were acquired and analyzed by conventional approaches and a validated parameterized diastolic filling (PDF) formalism. Isovolumic relaxation time decreased after weight loss in both groups ( P < 0.05). Septal peak early mitral annular velocity (E′) increased ( P < 0.01) and peak E-wave velocity/E′ decreased ( P < 0.05) after weight loss in the CR group. Based on the PDF-derived indexes, CR resulted in a decrease in global ventricular stiffness ( k) and increases in longitudinal (septal annulus motion) stored elastic strain ( x′o), peak force ( k′ x′o), and peak stored strain energy (1/2 k′ xoprime;2). In the Ex group, k was unchanged, although septal x′o and 1/2 k′ xo′2 increased significantly and k′ x′o ( P = 0.13) tended to increase. We conclude that weight loss, whether induced by CR or Ex, has salutary effects on diastolic function.

Glucokinase activators in diabetes management

Type 2 diabetes is a chronic metabolic disease that adversely affects both the quality and longevity of life. The disease is characterised by elevated blood glucose (hyperglycaemia) that is associated with microvascular complications and increased macrovascular risk. Existing oral agents, either alone or in combination, do not exhibit adequate or sustained glucose lowering efficacy in Type 2 diabetics. Consequently, there is an unmet medical need for improved antidiabetic agents which are both more effective at lowering glucose and which display sustained efficacy over a number of years. Such agents would allow present glycaemic treatment targets to be achieved with greater success. Glucokinase activators (GKAs) represent a novel class of glucose-lowering agents. Preclinical data supports the notion that these agents act to lower blood glucose through effects in both the liver and pancreas. It is predicted that this dual compartment mechanism of action of GKAs will translate to robust glucose lowering in diabetic patients. The potential benefits and risks associated with the pharmacological activation of glucokinase are evaluated. The status of GKAs in preclinical and clinical development is assessed are the future prospects of these agents.

Obesity reduces the bioavailability of nitric oxide in juveniles

OBJECTIVE

There is growing evidence that nitric oxide (NO) is critically involved in obesity and its clinical consequences like cardiovascular disease, hypertension and diabetes. We hypothesize that NO is already involved in the pathophysiology of juvenile obesity. We here determined the role of NO, its metabolites arginine and citrulline in obese and normal weight children.

DESIGN

We investigated 57 obese and 57 normal weight age- and gender-matched juveniles. Various clinical parameters as well as body measurements and intima media thickness were determined.

RESULTS

Obese juveniles revealed highly significant alterations in the NO pathway. NOX and citrulline were decreased in obese compared to normal weight juveniles and negatively correlated with body weight. Arginine was increased in obese juveniles and positively correlated with body weight. We found a significant negative correlation between NOX and oxidized low-density lipoprotein. Analysis of gamma-aminobutyric acid (GABA) revealed correlations with the NO pathway as NOX and citrulline were negatively correlated with GABA and arginine showed a positive correlation.

CONCLUSION

We show here that NO and its metabolites arginine and citrulline are already involved in juvenile obesity that may contribute to atherogenesis via reduced bioavailability of NO. Moreover, we identify GABA as a new parameter in the mechanism of obesity-related NO reduction.

Effects of long-term exercise and diet intervention on plasma adipokine concentrations

BACKGROUND

In a randomized, controlled, 2 x 2 factorial trial on the effect of long-term changes in diet and exercise, a significant reduction in body weight and fat mass was observed. Alterations in leptin and plasminogen activator inhibitor-1 concentrations were previously reported from this study.

OBJECTIVE

We examined the separate and combined effects of a 1-y exercise and diet intervention on several adipokines; adiponectin, interleukin-6 and -8, tumor necrosis factor-alpha, monocyte chemoattractant protein-1, hepatocyte growth factor, nerve growth factor, C-reactive protein, and resistin.

DESIGN

One hundred eighty-eight men with several risk factors for diabetes and cardiovascular disease were randomly allocated to 4 groups: diet, exercise, combined diet and exercise, and control.

RESULTS

Plasma adiponectin concentrations remained unchanged, whereas body mass index and fat mass decreased after dietary changes and an increase in physical activity. In the control group, adiponectin concentrations were reduced. Analyzed according to the factorial design, only diet intervention had a significant (P = 0.03) positive effect on plasma adiponectin relative to control, and this effect was largely explained by changes in fat mass. After adjustment for change in percentage body fat, there were significant positive effects on tumor necrosis factor-alpha in all 3 intervention groups (P = 0.01 for the diet group, 0.03 for the exercise group, and 0.05 for the combined diet and exercise group). Minor changes were observed for the other adipokines. Neither baseline concentrations of nor changes in adiponectin and plasminogen activator inhibitor-1 were significantly correlated to the other adipokines, whereas concentrations of and changes in the other adipokines were significantly correlated.

CONCLUSION

Diet intervention had a significant positive effect on adiponectin concentrations, which is largely explained by a reduction in fat mass.

Gestational diabetes, inflammation, and late vascular disease

Physiological changes of pregnancy include insulin resistance and activation of the innate immunity with an inflammatory response. The working hypothesis is that the sub-clinical inflammation associated with excessive adiposity may favor the development of gestational diabetes (GDM) and Type 2 diabetes and other metabolic abnormalities related to cardiovascular disease later in life. In this paper we review the complex interrelationship among inflammatory markers, metabolic syndrome, and endothelium dysfunction in women with GDM and discuss if women with previous GDM (pGDM) could be considered at risk for cardiovascular diseases. MEDLINE was searched for articles relating GDM and the adipokines (tumor necrosis factor-alpha and adiponectin) as well as the acute-phase inflammatory biomarker C-reactive protein that contribute to the development of diabetic pregnancy and vascular complications. However, to date, in pGDM women no prospective study is available, to corroborate the hypothesis that inflammatory pattern could be taken as predictor of cardiovascular disease later in life. Therefore, our paper should provide arguments to perform follow-up programs to prevent cardiovascular events in women with pGDM. Control of body weight, regular physical exercise are indeed powerful intervention tools able at improving insulin sensitivity and reduce sub-clinical inflammation, both involved in the pathogenesis of cardiovascular disease.

The potential anti-inflammatory benefits of improving physical fitness in hypertension

Hypertension is associated with an increased risk of stroke and atherosclerosis. In addition to elevated blood pressure, hypertension is characterized by neuroendocrine and immune activation, including elevated levels of C-reactive protein, inflammatory cytokines, and soluble adhesion molecules, which are predictive of morbidity and mortality outcomes. Pharmacological treatment for hypertension reduces blood pressure, but has limited effectiveness in reducing the accompanying inflammation and its associated morbidity and mortality. Exercise and diet interventions regularly show reductions in blood pressure in hypertensive individuals. Similar interventions in other populations show reductions in many inflammatory markers, but these effects have not been routinely examined in hypertensive individuals. The mechanisms through which exercise might exert an anti-inflammatory action include the sympathetic nervous system, the hypothalamic-pituitary-adrenal axis, as well as direct effects of blood pressure. Here, exercise is promoted as a potentially effective treatment for both the elevated blood pressure and chronic inflammation found in hypertension.

Obesity cardiomyopathy: diagnosis and therapeutic implications

Obesity is associated with an increased risk of heart failure. Apparently healthy obese individuals can, however, exhibit subclinical left ventricular dysfunction. The use of myocardial imaging techniques to detect this subclinical change could have important management implications with respect to initiating prophylactic therapy. In this Review, we evaluate possible pharmacologic and nonpharmacologic strategies for treating obesity cardiomyopathy in the context of currently understood mechanisms, including myocardial remodeling and small vessel disease, and more speculative mechanisms such as insulin resistance, and activation of the renin-angiotensin-aldosterone and sympathetic nervous systems.

Influence of epicardial adipose tissue and adipocytokine levels on cardiac abnormalities in visceral obesity

Adipocytokine levels and visceral adipose tissue (VAT) seem to be associated with some cardiac abnormalities and a role of visceral fat in predisposing to cardiac dysfunction, possibly through a low-grade state of inflammation, has been demonstrated. In this study we firstly show that elevated levels of both monocyte chemoattractant protein 1 (MCP-1) and soluble IL-6 receptor/interleukin-6 (sIL-6R/IL-6) complex are closely correlated with epicardial fat thickness.

Utility of the myocardial performance index in a population with high prevalences of obesity, diabetes, and hypertension: the strong heart study

INTRODUCTION

The myocardial performance index (MPI) introduced by Tei, a Doppler-derived echocardiographic measure that reflects both left ventricular (LV) systolic and diastolic function, has been shown to have prognostic value in several clinical settings, including myocardial infarction and congestive heart failure. There are scant data on the correlates and prognostic value of MPI in a population without overt cardiovascular (CV) disease.

METHODS

We investigated clinical and physiologic correlates of MPI, as assessed from echocardiographic Doppler recordings in 1,862 American Indian participants free of coronary or valvular disease or LV systolic dysfunction in the population-based strong heart study (SHS). We then assessed the prognostic value of MPI for incident CV events, including nonfatal stroke, coronary heart disease, congestive heart failure, and CV death.

RESULTS

The study population was 59 +/- 8 years old (66% women); 48% had diabetes, 44% hypertension, and 54% were obese. In univariable analyses, MPI (mean = 0.24 +/- 0.17) showed significant negative associations with creatinine clearance, C-reactive protein (CRP), LV ejection fraction (EF), mitral valve E- and A-wave velocities, cardiac index (CI), stroke index (SI) and stroke index/pulse pressure (SI/PP), and significant positive associations with serum creatinine and total peripheral resistance index (TPRI) (all P < 0.05). There were no significant associations of MPI with hypertension or diabetes status, systolic or diastolic blood pressure, body mass index, hemoglobin A1C or LV mass. After adjusting for age, sex, diabetes, and hypertension, MPI remained weakly but significantly correlated with CRP, EF, CI, SI, SI/PP, mitral E- and A-wave velocities, and TPRI. MPI did not predict fatal and nonfatal CV events (risk ratio 1.06 per unit MPI, 95% C.I. 0.56-2.04; P = 0.85) at a mean follow-up of 7.1 +/- 2.2 years.

CONCLUSIONS

In a population-based sample of adults with high prevalence of diabetes, hypertension, and obesity but without overt CV disease, MPI has weak associations with clinical and physiologic determinants of cardiac function. Moreover, MPI does not provide prognostic information for CV events in this population. Though conceptually attractive as a global measure of cardiac function, MPI has limited utility in a high-risk population without clinical CV disease.

C-reactive protein before and after weight loss in overweight women with and without polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is associated with reproductive and metabolic abnormalities. It is unknown whether overweight women with and without PCOS achieve similar benefits from weight loss for cardiovascular risk factors.

METHOD

Overweight body mass index-matched women with (n = 15) and without (n = 17) PCOS (weight, 95.3 +/- 17.6 kg; body mass index, 35.6 +/- 5.3 kg/m(2), mean +/- sd) followed an 8-wk weight loss regime.

RESULTS

All subjects had similar reductions in weight (3.9 +/- 3.6 kg, 3.8%, vs. 4.5 +/- 4.1 kg, 4.7%, respectively, for PCOS and non-PCOS), waist circumference, fat mass, triglycerides, free testosterone, and fasting and postprandial insulin. At baseline, C-reactive protein (CRP) between groups was not significantly different (5.5 +/- 3.1 mg/liter for PCOS vs. 4.9 +/- 3.0 mg/liter for non-PCOS). There was a significant interaction between PCOS status and CRP (P = 0.016) such that CRP decreased with weight loss for non-PCOS women (-1.2 +/- 1.8 mg/liter; P = 0.025) but not for PCOS women. For all women, the change in CRP correlated with the change in weight (r = 0.560; P = 0.003), fat mass (r = 0.477; P = 0.016), and postprandial insulin (r = 0.402; P = 0.046). Adiponectin, IL-6, and TNF-alpha were not significantly different between groups before or after weight loss. Only subjects with baseline CRP levels below the median (4.52 mg/liter) showed increases in adiponectin (0.98 +/- 1.3 microg/liter) (P = 0.015) and greater reductions in triglycerides (P = 0.001) with weight loss.

CONCLUSION

A 4-5% weight loss improved lipid, glucose, and insulin profiles in women with and without PCOS. This degree of weight loss was not effective in lowering CRP concentrations in PCOS women, suggesting that greater weight loss is required in this group to achieve equivalent cardiovascular benefit to non-PCOS women.

Metabolic effects of telmisartan and irbesartan in type 2 diabetic patients with metabolic syndrome treated with rosiglitazone

BACKGROUND AND OBJECTIVE

Angiotensin II receptor blockers represent a class of effective and well-tolerated orally active antihypertensive drugs in the general hypertensive population and in diabetic patients. The aim of our study was to investigate the metabolic effects of telmisartan and irbesartan in diabetic subjects treated with rosiglitazone.

METHODS

We evaluated 188 type 2 diabetic patients with metabolic syndrome. All patients took a fixed dose of 4 mg rosiglitazone/day. We administered 40 mg telmisartan/day or 150 mg irbesartan/day and evaluated their body mass index, glycosylated haemoglobin (HbA(1c)), fasting plasma glucose (FPG), fasting plasma insulin (FPI), homeostasis model assessment-index (Homa-IR), total cholesterol (TC), low density lipoprotein-cholesterol (LDL-C), high density lipoprotein-cholesterol, triglycerides, systolic blood pressure, diastolic blood pressure, adiponectin and resistin during 12 months of this treatment.

RESULTS AND DISCUSSION

In addition to a comparable antihypertensive effect for telmisartan and irbesartan after 6 and 12 months, both treatments were associated with a significant reduction in TC and LDL-C plasma levels compared with baseline. After 6 months of treatment, only the telmisartan group experienced a significant improvement in (HbA(1c)), FPG, Homa-IR, adiponectin and resistin compared with the baseline values, whereas both drug regimens were associated with a significant improvement in these parameters after 12 months. However, the improvements observed in the telmisartan group were significantly larger than that noted in the irbesartan group after 12 months of treatment. FPI significantly decreased only after 12 months of treatment in both groups, but again, the reduction was significantly larger in the telmisartan-treated subjects.

CONCLUSIONS

Telmisartan seemed to improve glycaemic and lipid control and metabolic parameters of the metabolic syndrome better than irbesartan. These differences could be relevant in the choice of therapy for this condition and diabetes.

Proinflammatory cytokines and cardiac abnormalities in uncomplicated obesity: relationship with abdominal fat deposition

BACKGROUND AND AIM

Obesity can be considered a state of chronic, low-grade inflammation. Particularly, visceral adipose tissue (VAT) seems to be an active compartment in pro-inflammatory molecule secretion. The possible existence of a correlation between circulating cytokines, their soluble receptors, abdominal fat accumulation and echocardiographic abnormalities in uncomplicated obesity was investigated.

METHODS AND RESULTS

Echocardiographic parameters, C-reactive protein (CRP), interleukin-6 (IL-6), soluble IL-6 receptor (sIL-6-R), tumor necrosis factor-alpha (TNF-alpha) and soluble TNF receptor I (TNFR-I) were assessed in 27 normotensive obese women (age 33.3+/-8.3 years; BMI 43.5+/-4.8 kg/m2) and 15 normal-weight controls (age 36.8+/-8.2 years; BMI 22.6+/-1.7 kg/m2). VAT was assessed by CT. The obese patients had higher serum IL-6 (p<0.01), sIL-6-R (p<0.0001), sIL-6-R/IL-6 complex (p<0.05), TNF-alpha (p<0.02), sTNF-alpha-RI (p<0.03) and CRP (p<0.0001) levels than normal women. Moreover, end-diastolic septum thickness (SW), end-diastolic posterior wall thickness (PW), absolute and indexed left ventricular mass, deceleration time (DT), myocardial performance index (MPI) and isovolumetric relaxation time (IVRT) were correlated with sIL-6-R, sIL-6-R/IL-6 complex and CRP levels. Interestingly, sIL-6-R, sIL-6-R/IL-6 complex, CRP, SW, PW, DT and MPI were higher in patients with a VAT area >130 cm2 than those with <130 cm2.

CONCLUSION

In normotensive obese women several pro-inflammatory molecules correlate with both echocardiographic abnormalities and the amount of intra-abdominal fat; these results may support a role for visceral fat in predisposing to cardiac dysfunction, possibly through a low-grade state of inflammation.

Right ventricular performance in severe obesity. Effect of weight loss

BACKGROUND

The effects of severe obesity on right ventricular function in the absence of associated cardiopulmonary disease are not well known. Right myocardial performance index (R-MPI) is an echocardiographic index to non-invasively assess the right ventricular function. The aim of our study was to assess R-MPI in individuals with severe but uncomplicated obesity before and after a significant weight loss induced by bariatric surgery.

PATIENTS AND METHODS

Fifteen obese females (OB) without cardiovascular and pulmonary diseases were examined. In all subjects, R-MPI was calculated by Doppler echocardiography as the sum of isovolumetric contraction time and isovolumetric relaxation time divided by ejection time. Furthermore, pulmonary function test (PFT) and 6-min walking test (6mWT) were performed. Ten healthy subjects with normal weight (HS) were also evaluated as controls. R-MPI, PFT and 6mWT were also re-evaluated one year later in 12 obese subjects treated with gastric banding after a consistent weight loss (> 20%).

RESULTS

A prolongation of R-MPI was found in OB before bariatric surgery in comparison to the HS (0.47 +/- 0.04 and 0.29 +/- 0.05, respectively; P < 0.001). R-MPI significantly improved in OB 12 months after surgery (0.32 +/- 0.03) and was no longer different from HS. R-MPI positively correlated to body mass index (BMI). A significant association was found between the reduction of BMI after bariatric surgery and the distance walked during the 6mWT.

CONCLUSIONS

These results show a right ventricular dysfunction in severe uncomplicated obesity, associated with an impaired functional capacity which recovers after consistent weight loss.

Normal coronary arteries in patients with systolic heart failure who have higher body mass index

BACKGROUND

Previous research has shown an association between higher body mass index (BMI) and lower mortality in patients with heart failure (HF).

METHODS

We compared the prevalence of angiographic coronary artery disease (CAD) and risk factors in obese versus non-obese patients with HF. Eighty-four consecutive patients with systolic HF who underwent coronary angiography in a single institution were categorized by BMI into non-obese (BMI < 30, n = 42) and obese (BMI >or= 30, n = 42) subjects.

RESULTS

Chi-square analysis demonstrated a greater prevalence of normal coronary arteries and a lesser prevalence of CAD in the obese patients compared with the non-obese patients (64% [27/42] of obese patients vs 43% [18/42] non-obese patients had normal coronary arteries, P < .05). Among the obese patients, the subgroup with normal coronary arteries had a higher BMI (39 vs 32, P < .001) and was younger (51 vs 63 years, P < .005) compared with those with CAD. Although the prevalence of significant CAD (>50% diameter stenosis) was similar between obese and non-obese patients, the obese subgroup had a lower high-density lipoprotein (39 vs 49 mg/dL, P < .05).

CONCLUSIONS

Angiographically normal coronary arteries were more prevalent in patients with systolic HF who have a higher BMI.

Effects of a Low-Fat versus a Low-Carbohydrate Diet on Adipocytokines in Obese Adults

BACKGROUND AND AIMS

There are few studies addressing the effect of weight loss on circulating levels of adipocytokines. The aim of our study was to determine whether different diets would have different weight loss effects and to examine the changes in adipocytokine levels.

METHODS

A population of 90 obesity non-diabetic outpatients was analyzed in a prospective way. The patients were randomly allocated to two groups: (a) diet I (low-fat diet), and (b) diet II (low-carbohydrate diet). At baseline and after 3 months on the diet, adipocytokines were evaluated.

RESULTS

43 patients were randomized to group I and 47 patients to diet group II. No differences were detected between weight loss in either group (3.3 +/- 0.51 vs. 4.4 +/- 0.6 kg; n.s.). In group I, a significant decrease in leptin levels was found. In group II, leptin and C-reactive protein (CRP) levels also decreased. The decrease in leptin levels was lower with diet I than II (16.4 vs. 22.8%; p < 0.05).

CONCLUSION

The serum leptin concentration decreased due to the 3-month intervention with low-fat and low-carbohydrate diets, without changes in other adipocytokines. The decrease in leptin and CRP levels were higher with a low-carbohydrate diet than a low-fat diet.

Role of Exercise and Metabolism in Heart Failure with Normal Ejection fraction

Left ventricular dysfunction associated with metabolic disorders has a number of features that might shed light on the integrity of heart failure with normal ejection fraction. First, although these patients may be dyspneic and have a normal ejection fraction, their diastolic dysfunction is not isolated. Both experimental models and sensitive new parameters in humans have shown abnormal systolic function, even though the less sensitive parameters (such as ejection fraction) become abnormal only with stress. Moreover, the mechanistic contributors to myocardial dysfunction, including structural changes and metabolic influences on the cardiac myocyte, interstitial fibrosis, vascular disease, and altered loading, are likely to influence systolic as much as diastolic function. The responses of systolic and diastolic heart failure to exercise training show analogies, particularly with respect to the importance of peripheral adaptation, as well as a similar training response. Together, these features are more supportive of a continuum of pathophysiology between systolic and diastolic heart failure, rather than the 2 representing discreet phenomena.

Alterations in Myocardial Characteristics Associated With Obesity: Detection, Mechanisms, and Implications

Hypertension, obstructive sleep apnea, and coronary artery disease all contribute to the myocardial dysfunction in obesity. However, the development of sensitive cardiac imaging techniques has enabled detection of myocardial structural and functional changes independently attributable to obesity, at the preclinical stage. This review will evaluate the evidence for myocardial disease in this setting, its significance, important mechanisms, preclinical detection, and possible therapeutic implications.

Changes in serum cytokine concentrations during the menopausal transition

OBJECTIVE

The purpose of the present study was to clarify the changes in serum concentrations of 17 cytokines in healthy women during the menopausal transition by using a multiplexed cytokine assay and to clarify the associations of these cytokines with serum estradiol concentration.

METHODS

Sixteen premenopausal, 54 perimenopausal and 52 postmenopausal women were enrolled in this study. Seventeen cytokines in serum samples were measured simultaneously using a Bio-Plex human cytokine 17-Plex assay.

RESULTS

Serum IL-6 concentration showed a weak positive correlation with age (r=0.196, p<0.05). Postmenopausal women for whom less than 5 years had passed since menopause showed significant (p<0.05) increase in serum concentrations of IL-2, GM-CSF and G-CSF, while serum IL-4 concentration was significantly (p<0.05) increased in postmenopausal women for whom more than 5 years had passed since menopause. Serum estradiol concentration showed a significant negative correlation with serum IL-6 concentration and weak negative correlations with serum concentrations of IL-2, IL-8 and GM-CSF.

CONCLUSION

We were able to simultaneously measure the levels of 17 cytokines using a highly sensitive cytokine assay, and we found that the changes in serum cytokine concentrations during the menopausal transition differed. We also found that serum IL-6 concentration during the menopausal transition was negatively correlated with serum estradiol concentration.

Diet/Exercise versus pioglitazone: effects of insulin sensitization with decreasing or increasing fat mass on adipokines and inflammatory markers

BACKGROUND

Plasma adipokine concentrations are variably related to fatness/insulin resistance and may act via endocrine mechanisms. We assessed the relationship among plasma adipokine concentrations and their relationship with insulin sensitivity and body composition in obese adults before and after insulin sensitization accomplished using diet/exercise or pioglitazone.

METHODS

Plasma adipokine concentrations, insulin sensitivity, and body composition were assessed in 39 upper-body obese insulin-resistant, nondiabetic adults before and after 19 wk of diet/exercise or 30 mg/d pioglitazone.

RESULTS

Diet/exercise reduced body fat and visceral fat and improved insulin sensitivity parameters; pioglitazone improved insulin sensitivity to a similar degree but increased body fat. Adiponectin increased more after pioglitazone (4770 +/- 487 vs. 8351 +/- 693.6 ng/ml, P < 0.001) than after diet/exercise (4704 +/- 367 to 5426 +/- 325.3 ng/ml, P < 0.01), whereas TNFalpha, IL-6, and resistin did not change. C-reactive protein decreased with diet/exercise. Adipokine concentrations were not correlated with each other at baseline or after insulin sensitization, except TNFalpha and IL-6 (r = 0.43, P < 0.05); IL-6 was inversely correlated with resistin. Only adiponectin was correlated (P < 0.05) with indices of insulin sensitivity. Adiponectin concentrations were inversely correlated with visceral fat and with sc fat depots in men but positively correlated with sc fat in women.

CONCLUSION

Plasma adipokine concentrations were not consistently interrelated, and only adiponectin displayed the expected relationship with insulin sensitivity and sensitization. These findings do not support an endocrine role for resistin, TNFalpha, and IL-6 in mediating changes in insulin resistance after diet/exercise or pioglitazone.

Effects of NO-1886 on inflammation-associated cytokines in high-fat/high-sucrose/high-cholesterol diet-fed miniature pigs

Inflammation, closely associated with obesity, is emerging as an important risk factor for the pathophysiological development of atherosclerosis and diabetes mellitus. Fat balance is critical in the aetiology of obesity. Lipoprotein lipase is an important enzyme in lipid metabolism. The aim of this study was to investigate the long-term effect of the lipoprotein lipase activator, NO-1886, on inflammation cytokines, adiposity and related diseases in miniature pigs fed a high-fat/high-sucrose/high-cholesterol diet (HFSC diet). Chinese Bama-miniature pigs were fed a control diet or HFSC diet with or without NO-1886 for 5 months. The levels of inflammation-associated cytokines were determined using the antibody arrays. Feeding of the HFSC diet to miniature pigs markedly increased the expression of inflammatory cytokines. On the other hand, supplementation of NO-1886 to HFSC diet decreased the expression of inflammatory cytokines significantly, protecting against the development of atherosclerosis and diabetes mellitus. NO-1886 may have a beneficial effect on the most inflammation-associated cytokines, and this effect may contribute to improving atherosclerosis and diabetes mellitus.

Subcutaneous adipose tissue cytokine production is not responsible for the restoration of systemic inflammation markers during weight loss

CONTEXT

It has been suggested that weight loss can improve systemic inflammation associated with obesity by decreasing the adipose production of pro-inflammatory cytokines. This suggestion, however, remains controversial.

OBJECTIVE

To analyse the effect of weight loss on peripheral inflammatory markers and subcutaneous adipocytokine production.

DESIGN

Patients were studied at baseline, at the end of the weight loss period, and after 2 weeks of weight stabilisation.

SUBJECTS

Nineteen morbid obese non-diabetic patients and 20 lean control subjects.

INTERVENTION

During the weight loss period patients followed a 6-week low-calorie diet.

MEASUREMENTS

Plasma levels of inflammatory markers, maximal in vitro whole-blood cytokine production, subcutaneous adipose tissue expression and content of several cytokines.

RESULTS

Obese subjects had higher circulating levels of C reactive protein (CRP), serum amyloid A (SAA), interleukin IL-6, IL-1 and soluble tumor necrosis factor receptors (sTNFR). Weight loss was associated with a significant decrease in CRP, SAA, leucocytes and plasma IL-6. Maximal in vitro cytokine production of IL-1 and sTNFR1 increased during this period. Weight loss did not induce significant changes in the adipose concentrations of IL-6, IL-1 or sTNF-receptors. However, adipose expression of IL-6, IL-1, TNFalpha, membrane cofactor protein-1 and adiponectin increased at the end of the weight loss period. During weight maintenance, circulating inflammatory parameters increased and in some cases returned to baseline.

CONCLUSIONS

A low-calorie diet is associated with an improvement in the systemic inflammatory status. This seems to be due to energy restriction rather than to adipose mass loss, since inflammatory levels return to baseline soon after weight stabilisation. Furthermore, a negative energy balance and fat mobilisation are associated with increased subcutaneous cytokine adipose expression.

Influence of weight loss on myocardial performance index

Obese patients may have a phase of asymptomatic left ventricular dysfunction. A combined myocardial performance index (MPI) has been demonstrated to be a useful index to estimate left ventricular function and to predict the prognosis of patients with heart failure. The objective of the study was to determine the influence of weight loss on MPI. A total of 18 obese patients (3 men, 15 women, mean age 49.6 +/- 5.5 years, body mass index [BMI] >30 kg/m(2)) were investigated in the study. All patients were treated with a multidisciplinary approach consisting of a hypocaloric diet and orlistat therapy (120 mg three times daily), and all of them underwent two-dimensional and Doppler echocardiographic examination two times before starting the study and after a period of weight loss. Using echo-Doppler methods, ejection fraction, peak velocities of early (E) and late (A) diastolic filling, the E/A ratio, deceleration time (DT), isovolumic contraction time (IVCT), isovolumic relaxation time, ejection time, and MPI were measured. The MPI was obtained by subtraction ejection time from the interval between cessation and onset of the mitral flow. All patients lost at least 10% of their initial body weight, with a mean decrease of 10.8 +/- 3.7 kg. This was associated with significant reductions in BMI with a mean decrease 4.5 +/- 1.4 kg/m(2). Compared with baseline, after weight loss the E/A ratio of 1.01 +/- 0.22 before treatment increased to 1.17 +/- 0.26 (P = 0.012), left ventricular mass index decreased from 88 +/- 23 to 82 +/- 19 g/m(2) (P = 0.028), IVCT from 71 +/- 20 to 53 +/- 30 ms (P = 0.004), DT from 233.65 +/- 38.14 to 196.72 +/- 47.73 s (P = 0.004), and MPI from 0.63 +/- 0.13 to 0.50 +/- 0.13 (P = 0.0001). Weight loss ameliorates MPI and seems to be a clinically relevant measurement of left ventricular global function, and may prove to be a valuable tool in assessing the risk of developing heart failure.

Association of C-reactive protein with the metabolic risk factors among young and middle-aged Koreans

We investigated the relationship between the clustering of risk factors for metabolic syndrome and the plasma C-reactive protein (CRP) concentration as measured by high-sensitive CRP assay. Body mass index, waist circumference, triglycerides (TGs), high-density lipoprotein cholesterol, fasting glucose, systolic and diastolic blood pressures, insulin, and CRP were measured in 1046 Korean adults (560 males; age, 18-64 years) in 2003 to 2004. There were statistically significant positive correlations for log CRP with body mass index, waist circumference, log TG, log insulin, and log homeostasis model assessment in both sexes after adjusting for age and smoking status. High-density lipoprotein cholesterol showed a significant negative correlation with log CRP in both sexes. For both sexes, the mean level of log CRP increased with increasing number of risk factors of metabolic syndrome (P for trend <.01 for males and <.001 for females). Stepwise multivariate linear regression analysis showed that waist circumference contributed the largest portion of the variance in CRP levels in both sexes. Log homeostasis model assessment and log TG were independently associated with log CRP levels only in females. These results indicate that CRP, a marker of inflammation that underlies atherosclerosis, is associated with the clustering of each metabolic syndrome risk factor and, furthermore, that abdominal obesity is the strongest predictor of CRP level in the Korean adult population.

Improving the dietary patterns of adolescents using a computer-based approach

The Centers for Disease Control and Prevention (CDC) recently reported that 16-33% of children and adolescents in the United States are overweight or obese, making this the number one nutritional disease of this group. The prevalence appears to be increasing annually, as are the associated consequences. Moreover, the CDC estimates that less than 50% of adolescents are physically active on a regular basis. In order to improve the health of these individuals, an intervention must be focused to modify these behaviors. Facilitating the understanding of proper nutrition and need for physical activity among adolescents will likely prevent health problems such as overweight and obesity and the development of chronic diseases later in life. Despite these concerns, adolescents remain one of the most underserved populations in terms of preventive services. In the past, health education interventions have shown increases in knowledge; however, the ultimate goal of these programs is to positively impact behavior. To accomplish this, we must focus on the learning styles of "today's" adolescents. Computer-based interventions allow for individualized strategies to promote healthy lifestyles. A computer-based intervention program has the potential to elicit a greater behavior change in comparison to a traditional didactic intervention program.

Mechanisms of endothelial dysfunction in obesity

Obesity is a chronic disease, whose incidence is alarmingly growing, affecting not only adults but also children and adolescents. It is associated with severe metabolic abnormalities and increased cardiovascular morbidity and mortality. Adipose tissue secretes a great number of hormones and cytokines that not only regulate substrate metabolism but may deeply and negatively influence endothelial physiology, a condition which may lead to the formation of the atherosclerotic plaque. In this review, the physiology of the endothelium is summarised and the mechanisms by which obesity, through the secretory products of adipose tissue, influences endothelial function are explained. A short description of methodological approaches to diagnose endothelial dysfunction is presented. The possible pathogenetic links between obesity and cardiovascular disease, mediated by oxidative stress, inflammation and endothelial dysfunction are described as well.

Epidemiological evidence for the role of physical activity in reducing risk of type 2 diabetes and cardiovascular disease

Epidemiological studies suggest that physically active individuals have a 30-50% lower risk of developing type 2 diabetes than do sedentary persons and that physical activity confers a similar risk reduction for coronary heart disease. Risk reductions are observed with as little as 30 min of moderate-intensity activity per day. Protective mechanisms of physical activity include the regulation of body weight; the reduction of insulin resistance, hypertension, atherogenic dyslipidemia, and inflammation; and the enhancement of insulin sensitivity, glycemic control, and fibrinolytic and endothelial function. Public health initiatives promoting moderate increases in physical activity may offer the best balance between efficacy and feasibility to improve metabolic and cardiovascular health in largely sedentary populations.